Now cats are a protective factor for MS?


Gustavsen M, Page C, Moen S, Bjølgerud A, Berg-Hansen P, Nygaard G, Sandvik L, Lie B, Celius E, Harbo HF. Environmental exposures and the risk of multiple sclerosis investigated in a Norwegian case¿control study. BMC Neurol. 2014 Oct 3;14(1):196. [Epub ahead of print]

Background Several environmental exposures, including infection with Epstein-Barr virus, low levels of vitamin D and smoking are established risk factors for multiple sclerosis (MS). Also, high hygienic standard and infection with parasites have been proposed to influence MS risk. The aim of this study was to investigate the influence of various environmental exposures on MS risk in a Norwegian cohort, focusing on factors during childhood related to the hygiene hypothesis.
Methods A questionnaire concerning environmental exposures, lifestyle, demographics and comorbidity was administrated to 756 Norwegian MS patients and 1090 healthy controls. Logistic regression was used to calculate odds ratio (OR) with 95% confidence interval (CI) for the risk of MS associated with the variables infectious mononucleosis, severe infection during childhood, vaccination and animals in the household during childhood. Age, gender, HLA-DRB1*15:01, smoking and infectious mononucleosis were included as covariates. General environmental exposures, including tobacco use, were also evaluated.
Results. Infectious mononucleosis was confirmed to be significantly associated with increased MS risk, also after adjusting for the covariates (OR=1.79, 95% CI: 1.12-2.87, p=0.016). The controls more often reported growing up with a cat and/or a dog in the household, and this was significant for ownership of cat also after adjusting for the covariates (OR=0.56, 95% CI: 0.40-0.78, p=0.001). More patients than controls reported smoking and fewer patients reported snuff use.
Conclusions In this Norwegian MS case-control study of environmental exposures, we replicate that infectious mononucleosis and smoking are associated with increased MS risk. Our data also indicate a protective effect on MS of exposure to cats during childhood, in accordance with the hypothesis that risk of autoimmune diseases like MS may increase with high hygienic standard.

The hygiene hypothesis is a hypothesis that states that a lack of early childhood exposure to infectious agents, symbiotic microorganisms (e.g. gut floraor probiotics), and parasites increases susceptibility to allergic diseases by suppressing the natural development of the immune system. In particular, the lack of exposure is thought to lead to defects in the establishment of immune tolerance

We all know about smoking and EBV infection so what next. If you look hard enough will you find a link and this one was having cats which reduced the risk by a half, will it reproduce.

So is it time to get a Moggie…maybe good for MS…However remember it could be bad for other things like allergies or your local bird life and Mice:-). I am sure many of you had cats in the house

The question is what are we going to link MS to next, high heels after all MS affects women more than men. Crazy idea? 

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  • Mousedoctor, I hate reading about studies such as eating too many sausages increase risk. A study by doctors in Germany. The truth is unless someone finds the cause it will go on and on. However, in 1978 when I was admitted to the National, along with was I a twin I was asked did I have dogs in childhood, by Professor MacDonald's registrar. I remember it well because I love dogs and always had them.

    • Unfortunately these things are the realms of sausage-factory stuff for clinical projects.

      It costs next to nothing to do a survey or an analysis of a database and so provide paper fodder for clinicians who need to pretend that they are doing research. Therefore you are stuck with them. Should we not report them?. Maybe be we have to get content and likewise when you read in the newspapers that blackcurrents stop MS, you will be able to read digest and see it for the load of old cobblers it is as you have desensitized.

      If you look hard enough you will find and if you put a statistical significance of P<0.05 means if you look at twenty things then by chance you will find something…hence I prattle on about ice cream consumption and MS to put these studies in prospective. The changes in risk of MS of any of these things are small. Some you can do nothing about some you can. We will now see a slew of papers from each country confirming or denying these results as we get more paper fodder.

      The government used to demonise smoking and you had smoking linked to every disease, now you have drinking as the un and comming demon and we will see a series of drink related papers such a drinking lowers your sperm count……drinking London water lowers your sperm count (too many oestrogens from plastics) and messes up your kettles, boilers, washing machines because the wateris so hard….do they have a campaign for water softeners?

      Wonder if they will do cars…they kill a lot more people than many of these risk factors…..maybe Range Rover drivers have a higher risk of MS:-), Fiat driver less?:-)

    • The trouble is MouseDoctor the clinicians are now using statistics to diagnose us. I'm not just talking about MS. If you are like me and have a history that doctors only see a couple of times in their career, you've got no chance. Lucky for me I've survived, but they should teach in medical school the figures can be misleading. I'm writing this on my laptop, any research into risk of MS with computer use?

    • Following on from the water mentioned above. I always use a water filter jug now and often boil my tap water to cook and drink. What is in tap water?

      Amber Wise, Kacie O’Brien, Tracey Woodruff. Are Oral Contraceptives a Significant Contributor to the Estrogenicity of Drinking Water?†. Environmental Science & Technology, 2010; 101026133329091 DOI: 10.1021/es1014482
      Men, women and children, and especially pregnant women excrete hormones in their urine, not just women taking the pill.

      There is a increased risk (studies show) of women taking the combined pill and getting MS. (Hellwig) If oral contraceptives do play a role in MS it's probably an effect of the hormones on the immune system?

    • I don't drink tap water as I'm allergic to chlorine (since a child) and I've never used oral contraceptives. And yes, I also grew up with dogs, I've never had EBV or measles, I spent most of my childhood outdoors, ate dirt blah blah blah etc etc..MS is a crapshoot, just about anything seems to be a risk factor, but it doesn't mean it is. Now if only I'd been surrounded by cats in high heels that drove Skodas, I'd never have got MS.

  • My family always had cats, I never smoked, Got a reasonable amount of sunshine, yet got MS. i did get a bad case of glandular fever as a teen. It's a shame its taken so long for the research world to focus on EBV. I hope the charcot project shows a tiny bit of promise. I know there will be bumps along the way, but a showing some efficacy would be a great start.

  • He he he, high heels is a good one – it would also correlate negatively with disease duration and with more disease activity on MRI :-).

  • I grew up on a farm and was exposed to all sorts so the hygiene hypothesis definitely doesn't apply to me. On cold nights it felt like we had more animals living in the house than outside at times.

  • I've had cats all my life and I even was very ill in my twenties with toxoplasmosis which I contracted from taking in a stray cat. So I feel confident that this theory does not apply to me.

  • A cat in high heels perhaps? I had moggies stray and otherwise from the age of 4 until my mid twenties, like all the other cat lovers here. I was asked in the AusImmune Study about my relationship with cats, natural or otherwise, this too with dogs and even the humble budgie. I live in the second sunniest State in Australia, I ended up in hospital with sun burn in my youth, a tan was natural, I never had glandular fever, but tests do show that I kissed the wrong boy in a sandpit somewhere. I still like the EBV theory, as a trigger factor at least, but work needs to be done in the genetic/ immune area to work out what goes wrong.

  • Dr. Grew up in Alaska. I got the MS Monster hitting me progressively just starting at the age of 50., my brother out did me with stage 4 cancer, my other siblings depression and one with suicide.
    So whats the common denominator of why I have MS? Have cats, dogs. Do not smoke, nor drive now. If low sunlight as a kid, other siblings would have ms

  • Lived in Malawi until aged 5, then lived in the west of Ireland but visited Malawi twice a year until 10, always had cats, brother died of fulminant MS at 38; I was diagnosed at 38 two years later.

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